CN107438573B

CN107438573B - Conveying system with conveyor belt

Info

Publication number: CN107438573B
Application number: CN201680021529.9A
Authority: CN
Inventors: P·E·小柯克帕特里克; A·L·马歇尔; J·F·兰德勒姆; R·L·罗森
Original assignee: Laitram LLC
Current assignee: Laitram LLC
Priority date: 2015-04-17
Filing date: 2016-03-11
Publication date: 2021-09-14
Anticipated expiration: 2036-03-11
Also published as: US9567164B2; BR112017021104A2; EP3283408B1; KR20170137086A; WO2016167907A1; US20160304293A1; CN107438573A; MX2017012038A; EP3283408A1; JP6799002B2; BR112017021104B1; JP2018513078A; EP3283408A4; CA2980128A1

Abstract

A conveyor for transferring articles off the end of a conveyor belt onto a discharge conveyor. The conveyor includes a conveyor belt overlapping the belt strands along a carryway. The belt strands are received in recesses below the conveying surface of the conveyor belt. The conveyor belt travels along an inner loop that is inside an outer loop surrounded by belt strands. The outer loop is separated from the inner loop at the end of the carryway. The belt strands extend along the carryway and separate articles from the conveyor belt to transfer articles to a downstream discharge conveyor or receive articles from an upstream feed conveyor.

Description

Conveying system with conveyor belt

Technical Field

The present invention relates generally to power-driven conveyors and, more particularly, to conveyors having conveyor belts that separate articles from the conveyor belt.

Background

When using a conveyor belt to discharge articles off the end of the conveyor belt onto a discharge conveyor, a stationary transfer plate positioned in the gap between the two conveyors is typically used. When the conveyor belt is stopped or there are no articles to unload, the belt articles can become trapped on the transfer plate. Sometimes, articles can be discharged from the conveyor belt directly to a downstream conveyor without an intervening transfer plate in the gap. However, the gap must be small enough to accommodate the feet (footprints) of the articles being discharged without them tipping over. When the conveyor belt has a long pitch or requires to pass over a large diameter sprocket at its discharge end, the gap is correspondingly large and can tip, skew, or trap items with small feet or small bottom features.

Disclosure of Invention

One version of a conveyor embodying features of the invention includes a conveyor belt having an outer article-supporting surface and forming an inner belt loop including an upper carryway segment along which the conveyor belt travels in a conveying direction. A plurality of parallel belt strands form an outer belt loop encircling an inner belt loop. The belt strands are recessed below the outer article-supporting surface of the conveyor belt on the upper carryway segment. In this manner, articles are conveyed on the carryway segment on the outer article-supporting surface of the conveyor belt.

Another version includes a carryway extending longitudinally in a conveying direction from an upstream end to a downstream end and a belt traveling along a portion of the carryway in the conveying direction and descending below the carryway at a belt separation location short of the downstream end. The conveyor belt has an outer article-supporting structure defining a conveying plane on which conveyed articles lie, and a plurality of longitudinal channels recessed below the conveying plane. Parallel belt strands received in the longitudinal channels travel along the carryway in the conveying direction to the downstream end. Conveyed articles are transferred from the conveyor belt to the plurality of belt strands at belt separation locations of the carryway.

Yet another version includes a first diverter element having an outer periphery and a second diverter element spaced from the first diverter element and also having an outer periphery. The conveyor belt has an outer conveying surface and forms an inner belt loop. The inner belt loop has an upper carryway extending in the conveying direction from a first diverting element at a first end of the carryway segment to a second diverting element at a second end of the carryway segment and a lower return segment between the second diverting element and the first diverting element. A first transition of the loop extends around a portion of the circumference of the first diverting element between the return section and the carryway section, and a second transition extends around a portion of the circumference of the second diverting element between the carryway section and the return section. A third diverting element having an outer periphery is disposed beyond the second end of the carryway segment in the conveying direction or beyond the first end of the carryway segment in a direction opposite the conveying direction. The parallel belt strands travel along the carryway segment in the conveying direction and form an outer belt loop having a third transition around a portion of the periphery of the third diverting element. Each of the strands travels along the length of the carryway segment and around a third diverting element at a third transition. The steering distance of the third steering element is smaller than the steering distance of the second steering element.

Drawings

FIG. 1 is a side view of a transfer conveyor embodying features of the invention;

FIG. 2 is an isometric view of a portion of a carryway of the conveyor of FIG. 1;

FIG. 3 is a cross-sectional end view of a portion of another version of a transfer conveyor embodying features of the invention;

FIG. 4 is a cross-sectional end view of a portion of yet another version of a transfer conveyor embodying features of the invention;

FIG. 5 is a cross-sectional end view of a portion of a fourth version of a transfer conveyor embodying features of the invention;

FIG. 6 is a side view of the discharge end of the transfer conveyor of FIG. 1, but with the conveyor belts driven individually;

FIG. 7 is a cross-sectional end view of the primary conveyor belt of FIG. 4 being driven by a secondary mesh belt;

FIG. 8 is a partial side view of a single set of secondary belt strands extending over a series of primary conveyor belts as in FIG. 1;

FIGS. 9A and 9B are side and top plan views of a transfer portion of another version of a transfer conveyor embodying features of the invention; and

fig. 10 is a side view of a version of a transfer conveyor having belt strands extending upstream to transfer articles from an infeed conveyor.

Detailed Description

Fig. 1 illustrates one version of a transfer conveyor embodying features of the invention. The conveyor 10 includes a primary conveyor belt 12 forming an inner belt loop 14 or loop and a secondary belt conveyor 16 forming an outer belt loop 18 or loop around the inner belt loop. The inner belt loop 14 has an upper carryway segment 20 that forms a portion of a carryway of a conveyor along which articles 22 are conveyed in a conveying direction 24. The primary conveyor belt 12 transitions on a transition segment 27 from the upper carryway segment 20 to the lower return segment 26 of the inner belt loop 14 about a turnaround element 28 located at a downstream end 30 of the carryway segment. The inner belt loop 14 also includes another transition section 29 around a diverter element 32 located at an upstream end 31 of the carryway segment 20. The primary conveyor belt 12 reverses direction from the lower return run 26 to the upper carryway segment 20 at an upstream transition 29. The downstream diverting element 28 may be, for example, a motor-driven sprocket or wheel set or a motorized drum. The upstream diverting element 32 may be, for example, an idler sprocket or a set of wheels or a roller or a skid (shoe). Alternatively, the belt 12 may be driven in the return section 26 and the two

diverting elements

28 and 32 may be idlers. Rollers 34 or shoes support the primary conveyor belt 12 in the primary return section 26.

In fig. 1, the primary conveyor belt 12 is shown as a modular conveyor belt constructed from a series of columns of one or more rigid belt modules 36 or slats that are coupled together at an articulated joint 38 between adjacent columns of belts. The modular conveyor belt 12 has a pitch P defined by the distance between successive hinge joints 38. The pitch P of the rigid belt modules, among other factors, sets a lower limit on the diameter of the diverting elements with which the conveyor belt can be used effectively. Modular belts constructed from rigid modules with long pitches require large diameter diverting elements. The larger steering element increases the steering distance R, measured along the transition around the steering element 28 from the tangent point C at which the loop separates from the carryway segment to the tangent point E at which the loop first becomes perpendicular to the carryway segment. Therefore, the tangents at points C and E are perpendicular to each other. Although the thickness, pitch and flexibility of the conveyor belt wrapped around the diverting element also affect the minimum spacing between end-to-end conveyors, for the purposes of this application, the diverting distance R is defined as the distance measured along the outer periphery of the diverting element. Thus, the turning distance as defined in the present application is a peripheral geometrical feature of the turning element, independent of the belt. For example, a diverting element with a circular periphery has a diverting distance R ═ rr R/2, where R is the radius of the diverting element, i.e. half the outer diameter. The turnaround distance R affects the degree to which one conveyor is spaced end-to-end from the other conveyor. A greater turnaround distance means a greater gap between adjacent end-to-end conveyors.

To minimize this gap, the secondary belt conveyor 16 forming the outer loop 18 comprises a plurality of parallel belt strands that are sufficiently flexible to wrap around a small diameter turning element 40, such as a static head bar (static nose bar) or powered rollers or wheels, on a transition 41, the transition 41 being tighter than the transition 27 of the primary belt. Examples of such flexible belt strands are narrow belts, narrow chains, V-belts, cable belts, toothed timing belts, such as by Manheim, Pennsylvania

Chainbands and strands of other materials manufactured by V-beads and sold by Fenner Drives Inc. The belt strands 16 forming the outer loop are supported in the secondary return section 47 by rollers 49 or slide rails. The deflection distance R' of the deflection element 40 of small diameter is much smaller than the deflection distance of the deflection element 28 of the primary belt. A small diameter diverting element 40 is positioned downstream of the carryway segment 20 of the primary belt loop 14. The secondary belt strands 16 ride in the conveying direction 24 along the carryway segment 20 in longitudinal channels on the top side of the primary conveyor belt 12. The belt strands 16 form a carryway extension 42 from a belt separation location 44 to a downstream diverting element 40 of the outer belt loop, and the primary conveyor belt 12 is at the belt separation location 4At 4, from the belt strands 16. Articles 22 riding on top of the primary conveyor belt 12 are transferred onto the belt strands 16 at belt separation locations 44. The small diameter diverter element 40 allows the discharge conveyor 46 to be positioned adjacent the belt strands 16 across the small gap 48 at the downstream end of the transfer conveyor 10 for smooth transfer of the articles 22 to the discharge conveyor. The gap 48 is much smaller than the gap required to separate the primary conveyor belt 12 itself from the discharge conveyor 46 without an intervening conveyor strand 16.

One version of the belt shown in fig. 1 is shown in fig. 2. The primary conveyor belt 50 is a modular plastic conveyor belt having embedded rollers 52 arranged to rotate about an axis 54 parallel to the conveying direction 24. The primary conveyor belt 50 is driven by a drive 56, which drive 56 comprises a motor 58 and a gearbox 59 connected to a drive shaft 60, on which drive shaft 60 a diverting element in the form of a sprocket is mounted. The article supporting rollers 52 are arranged in a longitudinal row. Longitudinal channels 62 are formed between the columns. Flexible belt strands 64 are received in the longitudinal channels 62. In this example, the belt strands 64 are joined by connecting bars 66 extending perpendicular to the conveying direction 24 along the hinge joints 38 between adjacent belt rows 68 to form a mesh belt 69 that provides additional product support. The connecting links 66 and belt strands 64 have apexes that are lower than the apexes of the article-supporting belt rollers 52 along the carryway segment of the primary belt. At the end of the carryway segment of the primary conveyor belt, the belt strands 64 separate the articles from the conveyor belt 50.

Fig. 3 shows another version of the belt of fig. 1. In this version, a portion of the width of the primary conveyor belt 70 is shown, the primary conveyor belt 70 having a plurality of longitudinal columns of article-supporting rollers 72, the article-supporting rollers 72 extending through the thickness of the belt. The apexes 74 of the rollers define a conveying plane 76. Drive structures 80 are formed in the recessed longitudinal channels 78 between the columns of rollers 72, with the drive structures 80 forming V-shaped grooves 81. Belt strands in the form of V-belts 82 are received in the grooves 81 and are frictionally driven along the carryway by the primary conveyor belt 70. The walls of the drive structure 80 forming the groove also help to cause the strands to travel along their path. The top surfaces 84 of the V-belt strands 82 are below the conveying plane 76 and do not contact conveyed articles. Articles supported atop the rollers 72 may be diverted toward or away from one side or the other of the belt 70 by diagonally oriented actuator rollers 86 in contact with the belt rollers 72 below the carryway segment of the conveyor belt 70. As the belt travels in the conveying direction, the belt rollers 72 roll on the diagonal actuator rollers 86. The actuator roller 86 rotates about a vertical axis 88 to change the direction of transfer from one side of the belt to the other. The V-belt 82 may be made of two materials, for example, a lower drive portion 83 made of a high friction material such as rubber or an elastomer to better drive the primary conveyor belt 70 and an upper article contacting portion 85 made of a low friction material to allow non-rigid articles to move smoothly across the conveyor without slipping.

In fig. 4, the primary conveyor belt 90 has a stacked roller configuration with the lower roller 92 engaging a pair of upper article-supporting rollers 93, the pair of upper article-supporting rollers 93 being supported at their ends in supports 95 extending upwardly from the conveyor belt 90 and rotatable about axis 91. The lower roller 92 extends below the belt 90 so that the rollers can be actuated by the actuator roller 86 to transfer articles as in fig. 3. The sets of three

rollers

92, 93 are arranged in longitudinal columns on either side of the recessed longitudinal channel 94. A belt strand 96 is received in each of the longitudinal channels 94. In this example, the belt strands 96 are shown as cable belts. The apex of the cable tie 96 is located below the apex of the article-supporting rollers 93. Fig. 7 shows a stacking roller conveyor belt 90 with the secondary mesh belt 69 of fig. 2. The mesh belt 69 is located below the apex of the top roller 93. The roller support 95 standing from the conveying belt 90 also serves as a driving structure that pushes the transverse connecting rod 66 to drive the mesh belt 69. The longitudinal strands 64 and the lateral connecting bars 66 of the mesh belt 69 also partially fill the longitudinal and lateral spaces between the sets of belt rollers.

The primary conveyor belt 100 in fig. 5 has a plurality of longitudinal rows of ribs 102 upstanding from its top side 104. The tops of the ribs 102 define a conveying plane 105. The articles conveyed by the belt are located on top of the ribs 102 along the carryway. Drive lugs 106 or teeth are formed at regular longitudinal intervals between laterally consecutive columns of ribs 102. Belt strands in the form of toothed belts 108, such as timing belts, are received in recesses 110 between successive columns of ribs 102. The drive lugs 106 of the conveyor belt 100 engage the drive-receiving surfaces of the teeth 112 on the bottom side of the toothed belt 108 to drive the belt strands along the carryway in the conveying direction.

In addition to the belt strands 114 being frictionally driven as in fig. 3 or rigidly driven by the primary conveyor belt as in fig. 5, the belt strands 114 may also be driven by their own drive 116 as shown in fig. 6. In this example, the belt strands are driven by a drive wheel 118 disposed below the diverting element 40 and inward away from the discharge conveyor. The buffer roller 120 applies tension to the belt strands 114 and increases the amount of wrap around the drive wheel 118. Alternatively,

pinch roller systems

122 and 118 are used to drive the belt strands 114. The belt strands may even be overdriven at a higher speed than the primary conveyor belt in order to provide tension in the carryway. Fig. 8 shows a single set of secondary belt strands 114 extending along a series of primary conveyor belts 124. The belt strands 114 bridge the continuous end-to-end primary conveyor belt 124 and convey articles across the intervening gap 126.

Fig. 9A and 9B show the transfer of articles to a downstream discharge conveyor 128 constructed from parallel belts 130, the belts 130 being separated by spaces 132. The downstream belt 130 diverts from the downstream return path to the downstream carryway about a diverting element 134, such as a set of sprockets or wheels. Parallel belt strands 136 forming the outer belt loop of the upstream conveyor extend into the spaces 132 between successive downstream belts 130 in a staggered arrangement such that the belt strands overlap the downstream belts in the conveying direction 24. The top article-conveying surface 137 of the belt strands 136 and the downstream belt 130 are substantially coplanar. The flexible belt strands 136 transition from the upstream carryway to the upstream returnway about a diverting element 138 located downstream of the diverting element 134 of the downstream belt. Thus, an article conveyed in the conveying direction 24 on top of a belt strand is transferred directly to a parallel downstream belt without crossing the gap between the upstream and downstream conveyors.

As shown in fig. 10, the transfer conveyor may be arranged to receive articles from an upstream feed conveyor 140. This arrangement is the reverse of the arrangement shown in figure 1. In this version, the outer belt loop 18 of the secondary belt conveyor 16 forms a carryway extension 142 that extends upstream from the upper carryway segment 20 to the small diameter diverting elements 40 near the discharge end of the infeed conveyor 140. Conveyed articles are conveyed from the belt strands 16 to the primary conveyor belt 12 at a belt merge location 144 at the upstream end of the carryway segment 20, with the conveyor belt merging with the belt strands at the belt merge location 144. The belt merging position is upstream of a belt splitting position 44 located at the downstream end of the carryway. On the carryway segment 20, the belt strands are located in longitudinal recesses below the plane of the outer article-supporting surface 146 of the conveyor belt so that articles are conveyed atop the primary conveyor belt 12. The outer belt loop may be arranged with small diameter diverting elements at the upstream and downstream ends of the carryway extension at both ends of the carryway segment of the primary belt for bidirectional operation with reversible conveying direction.

While features of the invention have been described with respect to various versions, other versions are possible. For example, the belt strands may include apertures that receive drive pins upstanding from the primary belt in a traction-feed drive engagement. As another example, the diverting elements for the conveyor belt strands need not be cylindrical strips; it may also be any type of structure that allows the belt strands to transition from an upper carryway to a lower returnway at tight radii. The various structures shown projecting upward from the top side of the conveyor belt (e.g., rollers, stacking rollers, ribs) are merely examples of article-supporting belt structures. Although the primary conveyor belt is described as a modular conveyor belt made of rigid, hinged modules, it is only one example. Other conveyor belts, such as hingeless, flexible conveyor belts, may also be used as the primary belt. Further, while fig. 1 shows the primary and secondary conveyor belts with separate return segments, in some configurations, the primary and secondary conveyor belts may be supported by return rollers or shoes in the same return path in which the primary conveyor belt is in contact with the secondary belt strands. Thus, as these examples suggest, the scope of the claims is not meant to be limited to the particular forms used in this specification.

Claims

1. A conveyor, comprising:

a carryway extending longitudinally in a conveying direction from an upstream end to a downstream end;

a conveyor belt traveling along a portion of the carryway in the conveying direction and descending below the carryway at a belt-dividing location short of the downstream end, the conveyor belt having an outer article-supporting structure defining a conveying plane on which conveyed articles lie and a plurality of longitudinal lanes that are recessed below the conveying plane;

a plurality of parallel belt strands received in the longitudinal channel and traveling along the carryway in a conveying direction to the downstream end;

wherein a conveyed article is transferred from the conveyor belt to the plurality of parallel belt strands at the belt break location of the carryway.

2. A conveyor as in claim 1 wherein the conveyor belt enters the carryway at a belt merge location upstream of the belt diverge location at which conveyed articles are conveyed from the plurality of parallel belt strands to the conveyor belt.

3. A conveyor as in claim 1 comprising a plurality of the conveyor belts arranged end-to-end in the conveying direction across an intervening gap and the plurality of parallel belt strands bridging the intervening gap.

4. A conveyor as in claim 1 further comprising one or more parallel downstream belts interleaved with the plurality of parallel belt strands to receive conveyed articles therefrom.

5. A conveyor as in claim 1 wherein the conveyor belt forms an inner belt loop and the plurality of parallel belt strands form an outer belt loop encircling the inner belt loop.

6. A conveyor as in claim 5 wherein the carryway comprises a carryway extension formed by the outer belt loop, the carryway extension extending in the conveying direction from the belt diverging location to the downstream end of the carryway, articles being conveyed on the carryway extension on the plurality of parallel belt strands.

7. A conveyor as in claim 1 further comprising a head bar at a downstream end of the carryway about which the plurality of parallel belt strands change direction.

8. The conveyor of claim 1, wherein the belt strand is selected from the group consisting of a cable belt, a V-belt, a chain belt, and a toothed belt.

9. A conveyor as in claim 1 comprising a first drive driving the conveyor belt and a second drive driving the plurality of parallel belt strands.

10. A conveyor as in claim 1 further comprising a connecting bar extending across the width of the conveyor belt over a portion of the carryway and connected to the plurality of parallel belt strands to form a web.

11. A conveyor as in claim 10 further comprising a drive structure upstanding from the conveyor belt that urges the connecting rod to drive the plurality of parallel belt strands in the conveying direction.

12. A conveyor as in claim 1 wherein the outer article-supporting structure comprises a plurality of columns of article-supporting rollers having apexes defining the conveying plane.

13. A conveyor as in claim 1 wherein the conveyor belt further comprises a drive structure in the longitudinal channel engaging the plurality of parallel belt strands along a portion of the carryway and driving the plurality of parallel belt strands in the conveying direction.

14. A conveyor as in claim 13 wherein the drive structure frictionally drives the plurality of parallel belt strands along the portion of the carryway in the conveying direction.

15. A conveyor as in claim 13 wherein the drive structure comprises a drive projection engaging a drive-receiving surface in the plurality of parallel belt strands to drive the plurality of parallel belt strands along the portion of the carryway in the conveying direction.

16. A conveyor as in claim 1 wherein the plurality of parallel belt strands have an upper portion made of a low friction material and a lower portion made of a high friction material.

17. A conveyor as in claim 1 comprising a plurality of the conveyor belts arranged end-to-end in the conveying direction, each forming a separate inner conveyor belt loop, and the plurality of parallel belt strands forming a single outer strand loop around the separate inner conveyor belt loop.

18. A conveyor as in claim 6 further comprising one or more parallel downstream belts interleaved with the plurality of parallel belt strands on the carryway extension to receive conveyed articles therefrom.

19. A conveyor as in claim 2 wherein the conveyor belt forms an inner belt loop and the plurality of parallel belt strands form an outer belt loop encircling the inner belt loop, the carryway comprising the carryway extension formed by the outer belt loop, the carryway extension extending in the conveying direction from the upstream end of the carryway to the belt-dividing location, articles being conveyed on the plurality of parallel belt strands on the carryway extension.

20. A conveyor as in claim 19 further comprising one or more parallel upstream belts interleaved with the plurality of parallel belt strands on the carryway extension to feed conveyed articles to the plurality of parallel belt strands.

21. A conveyor as in claim 1 wherein the conveying direction is reversible.

22. A conveyor as in claim 1 wherein the conveyor belt comprises a series of columns of rigid belt modules coupled together at hinge joints, the plurality of parallel belt strands being made of a flexible material.